The present invention relates in general to protective eye and face shields, and, in particular, to a new and useful facial shield for dental and medical use to shield the face of a practitioner from splatter, droplets and aerosol.
Practitioners in the field of dentistry have become increasingly aware of the possible dangers of contamination through splatter, droplets and aerosols, which may contain contagions from a patient. This concern has spread to the general medical community as the dangers of contracting diseases, such as herpes, hepatitis and aids, increase.
An article entitled "Controlling Aerosols, Splatter, Droplets" by Teri Reis-Schmidt, Dental Products Report, March 1988, analyzes the current thinking on protective attire for dental personnel. The article observes that high speed cutting instruments and ultrasonic scalers tend to produce splatter and aerosols in the operatory. Splatter droplets are defined as measuring more than fifty micrometers in diameter, while aerosols are defined as air suspended liquid or solid particles that measure less than fifty micrometers in diameter. Bacterial cells average one micrometer in diameter, while virus are considerably smaller. The article states that particles measuring less than five micrometers can penetrate lung passages all the way to the alveoli if they are inhaled.
While it is debated whether aerosols are capable of transmitting diseases, such as hepatitis B, it was observed in the article that common airborne aerosols should be differentiated from aerosols produced by high speed and high frequency equipment commonly used by a dentist, which aerosols may contain saliva and blood. While some experiments show that aerosolized blood and saliva from dental equipment does not transmit contagions, other experiments show that a simple cough or sneeze may produce airborne colony forming units of bacteria.
Diseases which can be transmitted via droplets from dental patients are identified by the article as including the common cold, hepatitis B, non-A/non-B hepatitis, influenza, measles (German and Rubeola), tuberculosis, staphylococcus and streptococcus infections and herpes infections, such as chicken pox (herpes zester), infectious mononucleosis (Epstein-Barr virus), herpetic whitlow (herpes simplex type I) and herpetic conjunctivitis (herpes simplex type I). Diseases that can be transmitted by respiratory roots include Legionellosis, mumps and pneumonia.
Despite the ongoing debate on which diseases can be transmitted through droplets, splatter or aerosols, it has become increasingly apparent that reasonable safety measures must be taken.
Although common eye wear, such as prescription glasses, may provide a modicum of protection, splatter and aerosol can easily circumvent such eye wear and contact the eyes of the practitioner. Such eye wear, of course, leaves the remainder of the face and, in particular, the nostrils and mouth, unprotected. Contamination to the practitioner's hair must also be considered.
Currently, face shields are known which cover the front, and wrap partially to the side of a practitioner's face. One shield, which was invented by the present inventor, even wraps partly around the bottom of the shield to provide some chin protection.
To be practical, however, all face shields must be sterilizable. This becomes increasingly difficult as the face shields become complex in structure. To be practical, the shields must also be perfectly transparent and optically non-distorting.
To dare, no full facial shield has all of the foregoing required attributes.